Towards the close of the century certain additions were made to the programme. In Ol. 65 (520 B.C.) the race in heavy armour was introduced at Olympia, and in 498 B.C. at Delphi. This innovation was clearly due to the growing importance of the heavy-armed infantry in Greek warfare. Greek sports were, as we have seen, in their origin practical and military, but with changed conditions of warfare they had lost their military character and become purely athletic. The chieftain no longer went to war in his chariot; his men no longer threw stones or light javelins. Individual warfare was giving place to the manœuvring of masses of heavy-armed troops. The introduction of the race in armour was an attempt to restore to athletics their practical character. The race was a diaulos, _i.e._ up the stadium and back to the starting-point, a distance of about four hundred yards. The men wore helmets, greaves, and round shields. At a later time the greaves were discarded, perhaps as a concession to athletes who regarded such a race as a spurious sort of athletics. Certainly the race never attained to the same prestige as the other events.
In Ol. 70 (500 B.C.) a mule chariot-race (ἀπήνη) was introduced, and in the next Olympiad a riding race for mares (κάλπη), in which the riders dismounted in the last lap and ran with their steeds. In both these events, which were discontinued after a short trial in Ol. 84, we may see the influence of the Elean nobility, whose wealth and power were derived largely from their horses and cattle. The introduction of mule chariot-races may have been partly due to the influence of the Lords of Sicily; the victory of Anaxilas is commemorated on the coins of Rhegium and Messana (Fig. 168). The κάλπη is of especial interest. Helbig has shown that the Hippeis of Athens and other Greek states in the sixth century were not cavalry soldiers in the strict sense of the word, but mounted infantry, the true successors of the Homeric chieftains.[78] Just as the latter went to war in their chariots, but dismounted in order to fight, leaving the chariot in charge of the charioteer, and remounting for flight or for pursuit, so the Hippeis of the sixth century merely used their horses for advance or for retreat, dismounting when they came into close contact with the foe, and leaving their horses with their squires, who accompanied them, either mounted behind them _en croupe_, or on horses of their own. The Homeric custom survived only in sports, in the ἀποβατής, whom we see represented on the frieze of the Parthenon in the act of dismounting; the later custom was represented for a brief time only by the κάλπη. As we have seen in discussing the race in armour, the system of individual warfare was passing away. Sparta had shown the superiority of masses of armed infantry. Previous to the Persian wars, Thessalian cavalry had already been employed by Peisistratus, and these served in the fifth century as the model on which corps of cavalry proper were organized in Athens and other states. But in 500 B.C. there were no cavalry in the Peloponnese, and the conservative nobles may well have regarded with jealousy a change which threatened to put them on a level with the ordinary foot-soldier. The introduction of the κάλπη then was an attempt to stimulate and encourage the older style of fighting. But the attempt was doomed to failure; the progress of military tactics was not to be checked by the Eleans, and while the hoplite race survived as long as the festival itself, the κάλπη was ignominiously abandoned in 444 B.C.